Prevent display from turning off due to inactivity when watching full screen video (windows 7)

"But there is a workaround:

mousejiggler.codeplex.com/

Make sure you use the Zen Jiggle mode to avoid any onscreen interference with your viewing pleasure."

"Maybe it depends on the browser and the operating system, but I can tell you that using Firefox 32.0.1 in Windows 7 64-bit, whenever a sound is played by the Flash plugin, it prevents the display from turning off. This can be seen by running powercfg -requests while a sound is playing (run cmd.exe as an administrator before typing the command):

C:\Windows\system32>powercfg -requests
DISPLAY:
[PROCESS] \Device\HarddiskVolume1\Program Files (x86)\Mozilla Firefox\firefox.exe

SYSTEM:
[DRIVER] IDT High Definition Audio CODEC (HDAUDIO\FUNC_01&VEN_111D&DEV_76DF&SUBSYS_1028053F&REV_1002\4&313bea4d&0&0001)
An audio stream is currently in use.

AWAYMODE:
None.

Two things are shown in this example output. It's the firefox.exe process under DISPLAY: that is preventing the display from turning off. The sound playing through the audio driver prevents the system from going to sleep.

I consider Firefox's behavior undesirable, as I seldom watch long YouTube videos, and I don't want every message notification from Facebook Chat to turn my screen on. The behavior can be changed by using a powercfg -REQUESTSOVERRIDE command, like this:

powercfg -REQUESTSOVERRIDE process ""\Device\HarddiskVolume1\Program Files (x86)\Mozilla Firefox\firefox.exe"" display

Type powercfg /? for help."

Maybe power saving looks for apps running in full screen mode but does not find any, because it's only the plug-in that's in full screen. Can you try setting the display mode of the browser to full screen (not maximized) before playing the video und check what happens then? Both Firefox and IE have full screen display modes.

"You could also a small utility called Full Throttle Override to automatically switch power plans whenever the Flash Player (or your favorite video player) is launched. (I added FlashPlayerPlugin_16_0_0_296.exe, for example).

You just have to make sure to set Turn off the display to Never in your High performance power plan. (Unfortunately the app doesn't support to switch to a specified power plan other than High performance)

I had a short test run using mplayer.exe and the utility successfully switched to High performance and back to my default power plan while having a memory footprint of about 9.3MB (on Windows 8.1 x64)"